Method of extracting wax from wax-containing hydrocarbons



Aug. 19 1924. 1,505,453

J. w WEIR METHOD OF EXTRACTING WAX FROM WAX CONTAINING HYDROCARBONS Filed Jan. 10. 1923 INVENTOR.

g WW

I Patented Aug. 19, 1924.

JAMES W. Wm, OF FILLMOEE, CALIFORNIA.

METHOD OF EXTBAGTING WAX FROM WAX-CONTAINING- EYDBOGARIBONS.

Application filed January 10, 1923. Serial No. 611,784.

v carbons, of which the following is a specification.

'ThlS application is in part a divisional continuatlon of my application Serial No. 540,060, filed February 20, 1922.

In the manufacture of lubricating oil from liquid hydrocarbons containing amorphous wax, which is a hydrocarbon substance of gummy consistency that will not flow freel at normal atmospheric temperature and as been described as resinous matter because of its general properties, it is necessary to extract the amorphous wax. This is diflicult, and has been accomplished in various ways, the first practical;

means being to dilute the liquid hydrocarbons with-a light hydrocarbon .of suitable gravity, chilling it to a proper temperature and allowing it to settle while cold, decanting off the wax-free oil after the wax has settled to the bottom of a settling tank.

It was discovered that this wax or resinous matter could be separated by centrifugal force in a suitable centrifugal machine, the first of which were of the basket type, and it was a slow, tedious and expensive operation to remove the wax from the machine. Afterwards a-continuous centrifuge machine was develorileld, but it was found impossible to remove t 's wax or resinous matter from the bowl and outlets of the machine continuously owing toits consistency. This made the centrifuge process impractical for commercial purposes.

It was later discovered that this wax or resinous matter could be floated out of the machine with a heavy immiscible substance such as water, brine or salt water. This method was found to be sub'ect to eontinuos interruptions by reason of e wax or resinous matter clo ging the outlets of the machine and not Eowing freely therefrom.

An improvement on this operation of purging the wax from the machine and causing it to flow freely from the machine has been made by the of steam or hot water applied in andto the wax outlets of the m e.

All of the above applies to well known methods, and 1t would not seem necessary to describe them in detail.

The wax so extracted by the above described methods or by any other method heretofore used has in a general way been a by-product 1n the manufacture of lubricatmg 011 was disposed of for purposes ofraw materlal or as a crude product to be further refined or'us'ed in the manufacture of other commodities.

I have found that I can continuously remove this wax from a centrifuge machine without interruptions and delays heretofore experienced in previously used methods, by the mtroduction into a centrifuge machine while continuously separating wax from a wax-containing hydrocarbon of a hot misclble substance at a point within the machine after the wax or resinous matter has been separated from the hydrocarbons, where it W111 mix with dissolve or melt the wax and cause it to iiow freely and continuously from the machine in mixture with the heated substance without such interruptions as have heretofore been encountered. The hot miscible substance can also be a hot hydrocarbon wax or any other grade of miscible wax which will flow freely when hot, or any other oil .or hydrocarbon in which the wax is miscible or soluble when heated, such as kerosene stock, gas oil or fuel oil, all of which are well known to those versed in the art.

The hot solvent or miscible substance used will preferably be a substance in which the extracted wax will be mixed for disposal as a finished product. For example, when no other means for disposal for this wax (which as noted beforeis a by-product in the manufacture of lubricating oil) is possible, it is mixed or blended with fuel oil and sold as such. By employing fuel oil as the hot substance in this method one step of the process of disposal, i. e. blending the fuel oil and wax, may be eliminated, with the saving of time and expense'incident thereto.

Another method of disposal of this wax is to blend it off with a heavy oil for the purpose of using it as a transmission lubricant. In such case the heavy oil may be used as the hot miscible substance described in this process, and the wax mixture flowing from the machine will be a finished commercial product, thereby eliminating the carbon wax as the miscible substance in the V process, the wax being extracted in the process may be used for this purpose, thereby making it possible in the process to remove the wax from the machine with the like hot wax being extracted, thus extracting the wax from the wax-containing hydrocarbon and removing it from the machine in combination with no foreign substance.

When complete or partial separation of 16 the wax from the heated substance is desirable or pi'ofitable, it maybe separated by distillation or any other well known method, according to the heated substance employed. The accompanying drawing illustrates diagrammatical structural features adapted for use in carrying out the operation as described in these specifications. The machine is so well known that means for operating same are not shown, but only those parts which are necessary to clearly illustrate the method described.

Referring to the drawing, the method of operating and accomplishing the purpose is as follows:

Oil containing wax is charged into feed tank 1, flows through central feed shaft 2 downward through outlet 3 below partially separated oil between discs at 4, where separation takes place. Pure oil passes upward from inner ends of discs through passage 5 and is discharged at outlet 6, from whence it overflows through ipe 7 for disposal.

At the same time t at oil containing wax is charged to feed tank 1, the hot substance employed is charged to feed tank 8 in quantities to accomplish the desired purpose, and flows through central feed shaft 9 to the lower portion of the machine with outlet at 10, where it .comes into intimate contact with, melts or dissolves and is mixed with the wax which has already been separated within the machine, and passes upward in mixture with same at outer part of bowl, 11., through upward passage 12 with outlet at "13, where 1t discharges through pipe 14 for disposal. t

- If it is not desirable or practical for the particular stock under treatment to use feed tank 8 as described through central feed shaft 9 and opening 10, feed tank 15 is provided and will be used instead of feed tank 8 for the hot substance employed, in which case the hot substance will be fed through feed tank 15 and inlet pipe 16 to wax outlet 13, where it will melt and mix with or dissolve the wax and cause it to flow freely from the outlet 14, which is the purpose of this invention.

' Outer part of bowl, 11, passage 12, outlet 13 through, to and including 14:, are the of the invention. It is essential that the oilbe kept pure'and free from substances used in the process, and this is done in my process, although the hot substance employed is introduced continuously during the continuous separation of wax in the machine.

It will be noted from the above that provisions have been made for the introduction of the hot substance employed into the .centrifuge machine at two different points, either one to be used as described, and it is not'essential that the machine be provided V With both.

It is to, be understood that the above description is for the purposes of illustration only, and the method is not necessarily limited thereto.

Having described the method invention, what is claimed as new and desired to be protected by Letters Patent is:

1. An improvement in the method of extracting wax from wax-containing hydro: carbons in a centrifuge machine, which re sides in the step of introducing a hot. 1i uid hydrocarbon into the centrifuge mac in exclusive] to the separated wax in the machine whi e continuously separating by centrifugal force further wax, which sald hot liquid hydrocarbon will melt and combine within the machine with the wax after it has been separated from the hydrocarbons,

to form a mixture that will flow freely and continuously from the machine, the 'hot liquid hydrocarbon and wax combined therewith at no time coming into contact with the wax-free hydrocarbons from which the wax has been extracted.

2. An improvement in the method of ex tracting wax from wax-containing hydrocarbons in a centrifuge machine, which resides in the step of introducing a hot liquid hydrocarbon solvent for the wax being separated into the centrifuge machine exclusively to the separated wax in the machine while continuously separating by centrifugal force further wax, which said hot liquid hydrocarbon solvent will melt and combine within the machine with the wax after it has been separated from the hydrocarbons, to form a mixture that will flow freely and continuously from the machine, the hot liquid hydrocarbon solvent and wax combined therewith at no time coming into contact with the wax-free hydrocarbons from which the wax has been extracted.

. lap- 3. An improvement in the method of extracting wax from wax-containing hydrocarbons in a centrifuge machine, which resides in the step of introducing a hot liquid wax, like unto the wax being separated, into the centrifuge machine excluslvely to the separated wax in the machine while continuously separating by centrifugal force further wax, which said hot liquid wax will melt, liquefy and combine within the machine with the wax after it has been separated from the hydrocarbons, to form a mixture that will flow freely and continuously from the machine, the hot introduced liquid wax and separated melted wax combined therewith at no time coming into contact with the wax-free hydrocarbons from which the wax has been extracted.

4:. The process of extracting wax from wax containing hydrocarbons which consists in separating the wax from the other hydrocarbons by centrifugal force, in a centrifuge machine, thus throwin the wax to the outer periphery of the mac ine, introducing hot liquid hydrocarbon into the machine and near its outer periphery while the machine is in operation, thus melting the wax with the hot liquid hydrocarbon and separately withdrawing the combined wax and hot hydrocarbon and the other hydrocarbons with which the wax was originally mixed.

\ 5. The process of extracting wax from wax containin hydrocarbons which consists in separating by centrifugal force in a centrifuge machine the wax from the wax,

containing hydrocarbon and continuously supplying to the outer periphery of the centrifuge machine hydrocarbons suificiently hot to keep the wax in a fluid state and continuously withdrawing through separated outlets of the machine, the fluid wax and the other hydrocarbons with which it was originally mixed. p

In testimony whereof I have signed my name to this specification.

Signed at Fillmore, in the county of Ventura, State of California, this fourth day of January, 1923.

JAMES W. WEIR. Witnesses:

F. L. GAY, S. A. WAGNER. 

